Suicide and lesser forms of self-aggression are significant health concerns with devastating personal, social, and economic costs. Both acute alcohol intoxication and chronic alcohol use are significant risk factors for self-aggressive acts across the spectrum of lethality. Evidence for these relationships, however, is based primarily on non-experimental retrospective research. Although informative, these studies are limited in their ability to support causal inferences, and information about the respective roles of acute and chronic alcohol use are difficult to disentangle using non-experimental approaches. For these reasons, we experimentally examined the effects of acute alcohol intoxication on self-aggressive behavior in non-alcoholic individuals using a novel laboratory paradigm (McCIoskey & Berman, in press). Results indicated that consumption of a "high dose" of alcohol (mean 0.10 BAC)facilitates self-aggressive behavior in men compared to their counterparts who consumed a placebo drink. In this application, we propose two studies to examine this relationship more precisely. The primary aim of Study 1 is to extend our initial findings by conducting a dose-response determination in both women (n = 80) and men (n = 80). Participants will be randomly assigned to receive a control drink or ETOH doses designed to achieve either 0.05g, 0.75g, or 0.10g/100 ml BAL. Sixty minutes after drink consumption, participants will be provided the opportunity to self-administer electric stimulation, with self-aggression defined as the level of shock selected. We hypothesize that self-aggressive behavior will increase as a function of dose, and that women will behave similarly to men when intoxicated. Study 2 will address whether self-aggressive behavior differs as a function of ascending versus descending blood alcohol concentration (BAC) limb. Women (n = 80) and men (n = 80) will receive either a (a) control drink or (b) alcohol to achieve a 0.10 g/100 ml BAL. Self-aggressive behavior will be assessed either on the ascending or descending limb at BAC = 0.08, and compared to yoked controls. Because the ascending limb is associated with greater cognitive impairment, we expect greater levels of self-aggression at that point of the biphasic curve.